/*
 * jQuery autocomplete plugin
 * Version 2.0.0  (2008-03-22)
 * @requires jQuery v1.1.1+
 *
 * Dual licensed under the MIT and GPL licenses:
 * http://www.opensource.org/licenses/mit-license.php
 * http://www.gnu.org/licenses/gpl.html
 *
 * Dylan Verheul
 * http://www.dyve.net/jquery
 *
 */
(function($) {
  /**
   * The autocompleter object
   */
  $.autocomplete = function(input, options) {

    // Create a link to self
    var me = this;
    // Create jQuery object for input element
    var $input = $(input).attr("autocomplete", "off");
    // Apply inputClass if necessary
    if (options.inputClass) {
      $input.addClass(options.inputClass);
    }

    // Create results
    var results = document.createElement("div");

    // Create jQuery object for results
    // var $results = $(results);
    var $results = $(results).hide().addClass(options.resultsClass).css("position", "absolute");
    if( options.width > 0 ) {
      $results.css("width", options.width);
    }

    // Add to body element
    $("body").append(results);

    input.autocompleter = me;

    var timeout = null;
    var prev = "";
    var active = -1;
    var cache = {};
    var keyb = false;
    var hasFocus = false;
    var lastKeyPressCode = null;
    var mouseDownOnSelect = false;
    var hidingResults = false;

    // flush cache
    function flushCache(){
      cache = {};
      cache.data = {};
      cache.length = 0;
    };

    // flush cache
    flushCache();

    // if there is a data array supplied
    if( options.data != null ){
      var sFirstChar = "", stMatchSets = {}, row = [];

      // no url was specified, we need to adjust the cache length to make sure it fits the local data store
      if (typeof options.url != "string") {
        options.cacheLength = 1;
      }

      // loop through the array and create a lookup structure
      for( var i=0; i < options.data.length; i++ ){
        // if row is a string, make an array otherwise just reference the array
        row = ((typeof options.data[i] == "string") ? [options.data[i]] : options.data[i]);

        // if the length is zero, don't add to list
        if( row[0].length > 0 ){
          // get the first character
          sFirstChar = row[0].substring(0, 1).toLowerCase();
          // if no lookup array for this character exists, look it up now
          if( !stMatchSets[sFirstChar] ) stMatchSets[sFirstChar] = [];
          // if the match is a string
          stMatchSets[sFirstChar].push(row);
        }
      }

      // add the data items to the cache
      for (var k in stMatchSets) {
        // increase the cache size
        options.cacheLength++;
        // add to the cache
        addToCache(k, stMatchSets[k]);
      }
    }

    $input
    .keydown(function(e) {
      // track last key pressed
      lastKeyPressCode = e.keyCode;
      switch(e.keyCode) {
        case 38: // up
          e.preventDefault();
          moveSelect(-1);
          break;
        case 40: // down
          e.preventDefault();
          moveSelect(1);
          break;
        case 9:  // tab
        case 13: // return
          if( selectCurrent() ){
            // make sure to blur off the current field
            $input.blur();
            e.preventDefault();
            // give focus with a small timeout (weird behaviour in FF)
            setTimeout(function() { $input.focus() }, 10);
          }
          break;
        default:
          active = -1;
          if (timeout) clearTimeout(timeout);
          timeout = setTimeout(onChange, options.delay);
          break;
      }
    })
    .focus(function(){
      // track whether the field has focus, we shouldn't process any results if the field no longer has focus
      hasFocus = true;
    })
    .blur(function() {
      // track whether the field has focus
      hasFocus = false;
      if (!mouseDownOnSelect) {
        hideResults();
      }
    });

    if(options.removeInitialValue)hideResultsNow();

    function onChange() {
      // ignore if the following keys are pressed: [del] [shift] [capslock]
      if( lastKeyPressCode == 46 || (lastKeyPressCode > 8 && lastKeyPressCode < 32) ) return $results.hide();
      var v = $input.val();
      if (v == prev) return;
      prev = v;
      if (v.length >= options.minChars) {
        $input.addClass(options.loadingClass);
        requestData(v);
      } else {
        $input.removeClass(options.loadingClass);
        $results.hide();
      }
    };

    function moveSelect(step) {

      var lis = $("li", results);
      if (!lis) return;

      active += step;

      if (active < 0) {
        active = 0;
      } else if (active >= lis.size()) {
        active = lis.size() - 1;
      }

      lis.removeClass("ac_over");

      $(lis[active]).addClass("ac_over");

      // Weird behaviour in IE
      // if (lis[active] && lis[active].scrollIntoView) {
      //  lis[active].scrollIntoView(false);
      // }

    };

    function selectCurrent() {
      var li = $("li.ac_over", results)[0];
      if (!li) {
        var $li = $("li", results);
        if (options.selectOnly) {
          if ($li.length == 1) li = $li[0];
        } else if (options.selectFirst) {
          li = $li[0];
        }
      }
      if (li) {
        selectItem(li);
        return true;
      } else {
        return false;
      }
    };

    function selectItem(li) {
      if (!li) {
        li = document.createElement("li");
        li.extra = [];
        li.selectValue = "";
      }
      var v = $.trim(li.selectValue ? li.selectValue : li.innerHTML);
      input.lastSelected = v;
      prev = v;
      $results.html("");
      $input.val(v);
      hideResultsNow();
      if (options.onItemSelect) {
        setTimeout(function() { options.onItemSelect(li) }, 1);
      }
    };

    // selects a portion of the input string
    function createSelection(start, end){
      // get a reference to the input element
      var field = $input.get(0);
      if( field.createTextRange ){
        var selRange = field.createTextRange();
        selRange.collapse(true);
        selRange.moveStart("character", start);
        selRange.moveEnd("character", end);
        selRange.select();
      } else if( field.setSelectionRange ){
        field.setSelectionRange(start, end);
      } else {
        if( field.selectionStart ){
          field.selectionStart = start;
          field.selectionEnd = end;
        }
      }
      field.focus();
    };

    // fills in the input box w/the first match (assumed to be the best match)
    function autoFill(sValue){
      // if the last user key pressed was backspace, don't autofill
      if( lastKeyPressCode != 8 ){
        // fill in the value (keep the case the user has typed)
        $input.val($input.val() + sValue.substring(prev.length));
        // select the portion of the value not typed by the user (so the next character will erase)
        createSelection(prev.length, sValue.length);
      }
    };

    function showResults() {
      // get the position of the input field right now (in case the DOM is shifted)
      var pos = findPos(input);
      // either use the specified width, or autocalculate based on form element
      var iWidth = (options.width > 0) ? options.width : $input.width();
      // reposition
      $results.css({
        width: parseInt(iWidth) + "px",
        top: (pos.y + input.offsetHeight) + "px",
        left: pos.x + "px"
      }).show();
    };

    function hideResults() {
      if (timeout) clearTimeout(timeout);
      timeout = setTimeout(hideResultsNow, 200);
    };

    function hideResultsNow() {
      if (hidingResults) {
        return;
      }
      hidingResults = true;

      if (timeout) {
        clearTimeout(timeout);
      }

      var v = $input.removeClass(options.loadingClass).val();

      if ($results.is(":visible")) {
        $results.hide();
      }

      if (options.mustMatch) {
        if (!input.lastSelected || input.lastSelected != v) {
          selectItem(null);
        }
      }

      hidingResults = false;
    };

    function receiveData(q, data) {
      if (data) {
        $input.removeClass(options.loadingClass);
        results.innerHTML = "";

        // if the field no longer has focus or if there are no matches, do not display the drop down
        if( !hasFocus || data.length == 0 ) return hideResultsNow();

        if ($.browser.msie) {
          // we put a styled iframe behind the calendar so HTML SELECT elements don't show through
          $results.append(document.createElement('iframe'));
        }
        results.appendChild(dataToDom(data));
        // autofill in the complete box w/the first match as long as the user hasn't entered in more data
        if( options.autoFill && ($input.val().toLowerCase() == q.toLowerCase()) ) autoFill(data[0][0]);
        showResults();
      } else {
        hideResultsNow();
      }
    };

    function parseData(data) {
      if (!data) return null;
      var parsed = [];
      var rows = data.split(options.lineSeparator);
      for (var i=0; i < rows.length; i++) {
        var row = $.trim(rows[i]);
        if (row) {
          parsed[parsed.length] = row.split(options.cellSeparator);
        }
      }
      return parsed;
    };

    function dataToDom(data) {
      var ul = document.createElement("ul");
      var num = data.length;

      // limited results to a max number
      if( (options.maxItemsToShow > 0) && (options.maxItemsToShow < num) ) num = options.maxItemsToShow;

      for (var i=0; i < num; i++) {
        var row = data[i];
        if (!row) continue;
        var li = document.createElement("li");
        if (options.formatItem) {
          li.innerHTML = options.formatItem(row, i, num);
          li.selectValue = row[0];
        } else {
          li.innerHTML = row[0];
          li.selectValue = row[0];
        }
        var extra = null;
        if (row.length > 1) {
          extra = [];
          for (var j=1; j < row.length; j++) {
            extra[extra.length] = row[j];
          }
        }
        li.extra = extra;
        ul.appendChild(li);

        $(li).hover(
          function() {
            var $this = $(this);
            active = $("li", ul).removeClass("ac_over").index($this[0]);
            $this.addClass("ac_over");
          },
          function() {
            $(this).removeClass("ac_over");
          }
        ).click(function(e) { 
          e.preventDefault();
          e.stopPropagation();
          selectItem(this)
        });

      }
      $(ul).mousedown(function() {
        mouseDownOnSelect = true;
      }).mouseup(function() {
        mouseDownOnSelect = false;
      });
      return ul;
    };

    function requestData(q) {
      if (!options.matchCase) q = q.toLowerCase();
      var data = options.cacheLength ? loadFromCache(q) : null;
      // recieve the cached data
      if (data) {
        receiveData(q, data);
      // if an AJAX url has been supplied, try loading the data now
      } else if( (typeof options.url == "string") && (options.url.length > 0) ){
        $.get(makeUrl(q), function(data) {
          data = parseData(data);
          addToCache(q, data);
          receiveData(q, data);
        });
      // if there's been no data found, remove the loading class
      } else {
        $input.removeClass(options.loadingClass);
      }
    };

    function makeUrl(q) {
      var sep = options.url.indexOf('?') == -1 ? '?' : '&'; 
      var url = options.url + sep + "q=" + encodeURI(q);
      for (var i in options.extraParams) {
        url += "&" + i + "=" + encodeURI(options.extraParams[i]);
      }
      return url;
    };

    function loadFromCache(q) {
      if (!q) return null;
      if (cache.data[q]) return cache.data[q];
      if (options.matchSubset) {
        for (var i = q.length - 1; i >= options.minChars; i--) {
          var qs = q.substr(0, i);
          var c = cache.data[qs];
          if (c) {
            var csub = [];
            for (var j = 0; j < c.length; j++) {
              var x = c[j];
              var x0 = x[0];
              if (matchSubset(x0, q)) {
                csub[csub.length] = x;
              }
            }
            return csub;
          }
        }
      }
      return null;
    };

    function matchSubset(s, sub) {
      if (!options.matchCase) s = s.toLowerCase();
      var i = s.indexOf(sub);
      if (i == -1) return false;
      return i == 0 || options.matchContains;
    };

    this.flushCache = function() {
      flushCache();
    };

    this.setExtraParams = function(p) {
      options.extraParams = p;
    };

    this.findValue = function(){
      var q = $input.val();

      if (!options.matchCase) q = q.toLowerCase();
      var data = options.cacheLength ? loadFromCache(q) : null;
      if (data) {
        findValueCallback(q, data);
      } else if( (typeof options.url == "string") && (options.url.length > 0) ){
        $.get(makeUrl(q), function(data) {
          data = parseData(data)
          addToCache(q, data);
          findValueCallback(q, data);
        });
      } else {
        // no matches
        findValueCallback(q, null);
      }
    }

    function findValueCallback(q, data){
      if (data) $input.removeClass(options.loadingClass);

      var num = (data) ? data.length : 0;
      var li = null;

      for (var i=0; i < num; i++) {
        var row = data[i];

        if( row[0].toLowerCase() == q.toLowerCase() ){
          li = document.createElement("li");
          if (options.formatItem) {
            li.innerHTML = options.formatItem(row, i, num);
            li.selectValue = row[0];
          } else {
            li.innerHTML = row[0];
            li.selectValue = row[0];
          }
          var extra = null;
          if( row.length > 1 ){
            extra = [];
            for (var j=1; j < row.length; j++) {
              extra[extra.length] = row[j];
            }
          }
          li.extra = extra;
        }
      }

      if( options.onFindValue ) setTimeout(function() { options.onFindValue(li) }, 1);
    }

    function addToCache(q, data) {
      if (!data || !q || !options.cacheLength) return;
      if (!cache.length || cache.length > options.cacheLength) {
        flushCache();
        cache.length++;
      } else if (!cache[q]) {
        cache.length++;
      }
      cache.data[q] = data;
    };

    function findPos(obj) {
      var curleft = obj.offsetLeft || 0;
      var curtop = obj.offsetTop || 0;
      while (obj = obj.offsetParent) {
        curleft += obj.offsetLeft
        curtop += obj.offsetTop
      }
      return {x:curleft,y:curtop};
    }
  }

  /**
   * The autocomplete plugin itself
   */
  $.fn.autocomplete = function(url, options, data) {

    // Make sure options exists
    options = options || {};
    // Set url as option
    options.url = url;
    // set some bulk local data
    options.data = ((typeof data == "object") && (data.constructor == Array)) ? data : null;

    // Set default values for required options (set global defaults in $.fn.autocomplete.defaults)
    options = $.extend({
      inputClass: "ac_input",
      resultsClass: "ac_results",
      lineSeparator: "\n",
      cellSeparator: "|",
      minChars: 1,
      delay: 400,
      matchCase: 0,
      matchSubset: 1,
      matchContains: 0,
      cacheLength: 1,
      mustMatch: 0,
      extraParams: {},
      loadingClass: "ac_loading",
      selectFirst: false,
      selectOnly: false,
      maxItemsToShow: -1,
      autoFill: false,
      removeInitialValue: true,
      width: 0
    }, $.fn.autocomplete.defaults, options);
      
    options.width = parseInt(options.width, 10);
    
    return this.each(function() {
      var input = this;
      new $.autocomplete(input, options);
    });

  }

})(jQuery);